Q&A - P5 Math

[concerned1970]

shawnlim88:

concerned1970:

4) Mr F had a sum of money. He gave half of his money plus $570 to his wife. He gave half of the remainder plus $420 to his parents. Then he gave half of the remainder to his daughter, Abby. He also bought a dress that cost $89 for Abby. If Mr F was left with $568, how much money did he have at first?

<------------------------------ WIFE --------------------------->
<---------------------------------------------------------->|570|
<------------------------>|420|<---------Parent------->|
<----------->|<--Abby->|
<568>|<89>
so:
<568>|<89>
|<--Abby-->|420|
<----Parent----->|
<---------------->|570|
<------WIFE ---------->

568 + 89(dress) = 657
abby gest 657
before giving abby: 657*2 = 1314

parents get: additional 420 = 1734
before giving parents: 1734*2= 3468

wife gets additional 570 : 4038
before giving wife: 4038*2 = 8076

answer: $8076

hope it helps.
i don't think a P5 student is able to solve this under exam condition.
:stupid: :stupid: :stupid:

Hi Shawn, my DS teacher did set this as exam ques, unfortunately he din get it right.

[jarenchuatw]

Need help in the following 2 questions:

1. To number the pages of a story book, 642 digits (0,1,2…9) are needed. How many pages does the story book have?
2. A total of 683 balls with 3 different colours, brown, green and white are arranged in the pattern of BBGGGWWWW. What is the colour of the last ball?

[vsk]

Hi everyone, i would like to seek your help in doing this question.


A watch and a pen cost $105. If 3 pens cost $27 more than the watch, find the cost of such 2 watches?

thks :thankyou:

[MathIzzzFun]

vsk:

Hi everyone, i would like to seek your help in doing this question.


A watch and a pen cost $105. If 3 pens cost $27 more than the watch, find the cost of such 2 watches?

thks :thankyou:

3 pens = 1 watch + $27

1 watch + 1 pen = $105
3 watches + 3 pens = $315
3 watches + (1 watch + $27) = $315
1 watch --> $72

cheers.

[vsk]

Thank you MathIzzzFun for the solution. It really helped. :thankyou:

[vsk]

Hi everyone. I need your help in solving this question.Thks.


The total cost of 9 forks and 5 knives cost $71. the total cost of 3 forks and 3 knives is $33. find the difference in cost between a fork and a knife.





:thankyou:

[AtoZ]

Hi there, I need your help!


In a library, the number of adults was 3/5 of the number of children at first. Then 6 adults and 4 children came in and the number of adults became 3/4 of the number of children. How many people were at the library at first?

Thank you!

[MathIzzzFun]

AtoZ:

Hi there, I need your help!


In a library, the number of adults was 3/5 of the number of children at first. Then 6 adults and 4 children came in and the number of adults became 3/4 of the number of children. How many people were at the library at first?

Thank you!

at first,
adults --> 3 units
children --> 5 units
total --> 8 units

in the end,
adults --> 3 units + 6 = 3 * (1 unit +2)
children --> 4 * (1 unit + 2) = 4 units + 8


4 children added in the end,
so, 5 units + 4 = 4 units + 8
1 unit --> 4

At first, total number of people at the library --> 8 x 4 = 32

cheers.

[AtoZ]

MathIzzzFun:

AtoZ:

Hi there, I need your help!


In a library, the number of adults was 3/5 of the number of children at first. Then 6 adults and 4 children came in and the number of adults became 3/4 of the number of children. How many people were at the library at first?

Thank you!

at first,
adults --> 3 units
children --> 5 units
total --> 8 units

in the end,
adults --> 3 units + 6 = 3 * (1 unit +2)
children --> 4 * (1 unit + 2) = 4 units + 8


4 children added in the end,
so, 5 units + 4 = 4 units + 8
1 unit --> 4

At first, total number of people at the library --> 8 x 4 = 32

cheers.

Many thanks, MathIzzzFun!

Btw, is the question a P5 standard?

[MathIzzzFun]

AtoZ:

MathIzzzFun:

[quote=\"AtoZ\"]Hi there, I need your help!


In a library, the number of adults was 3/5 of the number of children at first. Then 6 adults and 4 children came in and the number of adults became 3/4 of the number of children. How many people were at the library at first?

Thank you!

at first,
adults --> 3 units
children --> 5 units
total --> 8 units

in the end,
adults --> 3 units + 6 = 3 * (1 unit +2)
children --> 4 * (1 unit + 2) = 4 units + 8


4 children added in the end,
so, 5 units + 4 = 4 units + 8
1 unit --> 4

At first, total number of people at the library --> 8 x 4 = 32

cheers.

Many thanks, MathIzzzFun!

Btw, is the question a P5 standard?[/quote]
yes

cheers.